The present invention relates to an inflatable device incorporating a plurality of bladders to provide added safety in the event of a puncture.
Inflatables are used for a vast range of purposes including inflatable boats, personal floatation devices (PFD) and various recreational, commercial or military products. In particular, the function of most inflatable devices is entirely dependent on the ability of the device to hold air. In many applications it is desirable for a device to inflate even in the presence of some type of physical damage to the device.
It is well known to provide these inflatable devices with separate compartments or bladders that are separately inflatable and who""s combined inflation volume is required to complete the filling of the confined space formed by the outer skin. In many applications the skin also forms a wall of the compartments or bladder(s). e.g. inflatable rafts, some air mattresses etc. Applicant is aware of an inflatable pool toy (kayak, it is believe) where inside the outer shape forming skin were at least 3 bladders (the skin formed the wall or some of the walls of each bladder). The main bladder (may have been a pair of side by side main bladders, Applicant is not sure) was inflated to form the shape of the toy. Inside the toy were a pair of separate independent auxiliary small bladders that had minimum exposure to the skin of the toy (probably less than about 30%) and their inflation did not significantly change the shape of the toy. The concept was that if the main bladder(s) were puncture these independent bladders were sufficient to support the person but obviously lower in the water, i.e. with the main bladder(s) inflated the toy floated with about 70% above water when a child was on it, with only the independent bladders the toy would likely still support the child but would sink to just below the surface of the water so that it applied maximum buoyancy. The auxiliary small bladders were filled through their own separate fillers before use (and when inflated these bladders simply occupied space in the toy). It is possible not to inflate these auxiliary bladders but if the main bladder were punctured the device would tend to sink until the small auxiliary bladders were filled and for this toy would not provide for the safety of the child who may not have the capability to inflate these small bladders.
It is the main objective of the present invention to provide an inflatable system whereby in the event of damage to the device the inflatable may retain the ability to hold air and function as intended.
Broadly the present invention relates to an inflatable device comprising a shape defining shell containing at least two separate inflatable bladders, each said bladder having and inflation means capable of inflating its respective bladder, each said bladder being of a size when fully inflated to fully inflate said shell, at least one of said being an initially deflated bladder which in deflated condition is folded upon itself to provide a folded end on said deflated bladder, said folded end positioned facing the other of said at least two bladders and said deflated bladder being positioned within said shell so that it occupies no more than 50% of the total cross sectional area of the major surface of said shell when said shell is fully inflated by one of said bladders.
Preferably said another of said deflated bladder is positioned so that said deflated bladder occupies less than 30% of said cross sectional area.
Preferably a divider panel is interposed between the bladders.
Preferably said folded on itself comprise a portion of said deflated bladder being tucked inside other portion of said deflated bladder.
Preferably each of said at least two bladders are deflated bladders and each is folded upon itself to provide a folded end on each said deflated bladder, said folded ends on each of said deflated bladders positioned adjacent to each other, said divider panel being symmetrically positioned with respect to said adjacent folded ends of said bladders and overlapping each of said bladders in the directions parallel to said folded ends and perpendicular to said folded ends so that during inflation of one of said bladder, said one of said bladders being inflated may slide past the adjacent fold edge an adjacent of said bladders.
Preferably said inflating means comprises a sealable manual inflating tube.